What Ate What?

[MarcoSr]

This is a coprolite from the Ypresian, Eocene of Virginia from a near shore, marine environment. I will say that the specimen is a coprolite with multiple vertebrae as I have found many thousands of both coprolites and vertebrae from this site (no exaggeration). The specimen is 8mm and the vertebrae are around 1mm.

I believe that the candidates for the eaters are shark, ray and fish. Although I do find a very large number of sea snake vertebrae in the fauna.

I believe that the eaten could be shark, ray or fish. The vertebrae id is open for debate.

I know sharks eat/ate other sharks, rays and fishes.

I know fishes eat/ate other fishes but what about sharks or rays?

I don’t know if rays eat/ate other rays, fishes or sharks. I know sawfishes eat/ate fishes.

What did sea snakes eat? What would a sea snake coprolite look like?

Can you answer any of these questions?

Bottom line, what ate what??????? I think I know. What do you think?

Coprolite views:

Some close-up views:

Marco Sr.

Edited October 16, 2014 by MarcoSr

[Al Dente]

That's a nice specimen. I think the vertebrae are from a bony fish because of the thin buttressing bone pattern. I can say with some confidence that it is not a snake coprolite. I used to keep snakes and they are pretty efficient at digesting bone.

[fossilized6s]

Adding to Eric's statement, snakes turn bone into a fine powder and it would not recognizable.

Cool piece Marco!

Also, wouldn't shark coprolite be spiral shaped? You taught me that.

[ashcraft]

All I can add looking at those specimens is ouch! Passing those looks a little painful to me.

Brent Ashcraft

[non-remanié]

Very odd and puzzling piece. How many other coprolites do you have from the site that show vertebrate remains apparent on the surface like this? Do any show similar fairly intact vertebrae on the surface? There are a lot of issues to consider in this taphonomic puzzle.

[MarcoSr]

Very odd and puzzling piece. How many other coprolites do you have from the site that show vertebrate remains apparent on the surface like this? Do any show similar fairly intact vertebrae on the surface? There are a lot of issues to consider in this taphonomic puzzle.

Steve

I probably have at least several hundred coprolites with surface evidence of bones or vertebrae from this site. Most only show a few bones or a single vertebra. I've found easily over 10 thousand coprolites and 20 thousand or more fish, shark and ray vertebrae from the site. I have hundreds of shark coprolites with the impressed spiral grove and a good number of the rolled/wrapped variety. I have probably over three hundred sea snake vertebrae also. The preservation allowed the coprolites and vertebrae to be in pristine condition.

Marco Sr.

[MarcoSr]

On 10/11/2014 at 7:30 PM, Al Dente said:

That's a nice specimen. I think the vertebrae are from a bony fish because of the thin buttressing bone pattern. I can say with some confidence that it is not a snake coprolite. I used to keep snakes and they are pretty efficient at digesting bone.

Eric

I questioned whether these vertebrae might be lamnoid-type primitive shark vertebrae which closely resembled fish but had distinct foramina and no fossilized transverse processes or neural or hemal spines. However there are two places where it looks like there might be processes or spines and there is that other piece of bone in the one picture. Also, the vertebrae are only 1mm which would seem too small for most sharks and rays, although still possible. But I agree that the most determining feature is the thin buttressing bone pattern which looks like bony fish.

Marco Sr.

[MarcoSr]

Adding to Eric's statement, snakes turn bone into a fine powder and it would not recognizable.

Cool piece Marco!

Also, wouldn't shark coprolite be spiral shaped? You taught me that.

All I can add looking at those specimens is ouch! Passing those looks a little painful to me.

Brent Ashcraft

Charlie and Brent

It is possible that the entire coprolite didn't fossilize so the original coprolite may have had the vertebrae completely covered and may have looked quite different. However, of the thousands of coprolites that I have from the site, the shape of the original coprolites looks like they were preserved intact.

Marco Sr.

[tmaier]

Here is an example (9mm) of an impressed spiral grove coprolite from the site which I believe is definitely shark. I haven't found any impressed spiral grove examples with visible bones or vertebrae.

Want to run some through a saw, and examine the inside? (since you have so many, some could be used for testing).

I use a Dremmel with a cut-off disk, a very thin stone for cutting steel and rock. Often with something that small I have to fore go cutting it directly in half, and can only make a cross-section by grind off one side.

Edited October 12, 2014 by tmaier

[sixgill pete]

Marco, that is an impressive piece of ...... coprolite. I also, would not have taken this for shark poop, possibly not coprolite of any kind. Kind of brings a new light to the phrase "the proof is in the pudding"

[MarcoSr]

Marco, that is an impressive piece of ...... coprolite. I also, would not have taken this for shark poop, possibly not coprolite of any kind. Kind of brings a new light to the phrase "the proof is in the pudding"

Don

I have found so many of these coprolites now, it is much easier to recognize them and to distinguish at least some of them. I have a large number that are round versus cigar shaped like the two I posted here. Some of the round ones have bones and vertebrae also. I believe that the round ones are from fish. I believe that there were several types of fish that didn't process the fish bones from their prey much at all before expelling the material. Also they were the type of fish that swallowed their prey whole because the bones and vertebrae are mostly intact in the coprolite. I don't see recognizable bones and vertebrae in the rolled/wrapped shark coprolite variety. However I do see lots of flecks of material in some of them which I believe are bone flecks.

Marco Sr.

[MarcoSr]

Want to run some through a saw, and examine the inside? (since you have so many, some could be used for testing).

I use a Dremmel with a cut-off disk, a very thin stone for cutting steel and rock. Often with something that small I have to fore go cutting it directly in half, and can only make a cross-section by grind off one side.

I often wanted to section some of these. With the coprolites that I find that are broken, I don't see anything at the broken face. The shark coprolites of the rolled/wrapped variety will show the rolls/wraps which you can't see with the complete coprolite, unless broken, where you at most see a seam. But I haven't thin sectioned any of these and looked at the thin sections under high magnification. Could you polish a few of these after cutting? Then you or I could take some pictures. But again I'm not really expecting to see a lot. If you PM me with your address, I'll send you a group of them.

Marco Sr.

[MarcoSr]

Here are a couple more with bone and vertebrae in them. The first is flattened somewhat. The second has vertebrae of different sizes.

Edit: I originally thought that the below coprolites  were Spiral Valve with impressed spiral grooves produced by sharks.  However closer examination showed that they were Segmented produced by actinopterygian fishes.  If Spiral Valve, there is a single groove that spirals around the coprolite.  Segmented have a number of different grooves that close upon themselves.

 

Scroll Valve - outer portion wrapped over interior (I included one end picture so you could see the wrapping):

Marco Sr.

Edited June 24, 2019 by MarcoSr
Changed Spiral Valve to Segmented

[tmaier]

I no longer have access to good optics. Still, since the bone is petrified black and the coprolite is white, it should be visible with just a hand lens.

It seems possible that the creature that is leaving the spiral groove coprolites is not the same \creature that is leaving the ones with the whole vertebra in them. So attempting to find them in sections may not yield any more information. You never know until you try.

[MarcoSr]

On 10/13/2014 at 11:39 AM, tmaier said:

I no longer have access to good optics. Still, since the bone is petrified black and the coprolite is white, it should be visible with just a hand lens.

It seems possible that the creature that is leaving the spiral groove coprolites is not the same \creature that is leaving the ones with the whole vertebra in them. So attempting to find them in sections may not yield any more information. You never know until you try.

I believe that the creature leaving the coprolites with the vertebrae in them is a bony fish and that the spiral groove coprolites are shark.

Marco Sr.

[fossilized6s]

Honestly i think these coprolites aren't in their "original form", and Marco as you suggested earlier, maybe the copro as a whole didn't fossilize, leaving these. And ultimately these are a glimpse to the inside of your whole copros. To be certain of the family of the consumer/depositor may be impossible. But i do think the idea that these verts aren't fragments does suggest being eaten whole.

Edited October 13, 2014 by fossilized6s

[tmaier]

I wonder is scales could be found in the details.

[MarcoSr]

On 10/13/2014 at 1:52 PM, fossilized6s said:

Honestly i think these coprolites aren't in their "original form", and Marco as you suggested earlier, maybe the copro as a whole didn't fossilize, leaving these. And ultimately these are a glimpse to the inside of your whole copros. To be certain of the family of the consumer/depositor may be impossible. But i do think the idea that these verts aren't fragments does suggest being eaten whole.

Charlie

I don't know if the vertebrae would have gotten through a shark's digestive system looking as pristine as they do. Hundreds of coprolites, that I believe I can identify as shark from this site, don't have intact vertebrae visible on the surface. Looking more closely at them I do see flecks or an occasional very small bone fragment in some. I see more bones and larger bone fragments in coprolites from the site which I'm pretty sure are from bony fish. So I really do believe the coprolites are from bony fish versus sharks. I think that you are definitely correct that the coprolites aren't in their original form. I can't imagine a digestive system passing something with all those bones sticking out.

However I'm starting to think that there may be another possibility. I am now definitely questioning my own statement of "100% certainty that the specimen is a coprolite with multiple vertebrae". I have been doing some reading on fossilized gastric residues, which are fossilized regurgitated remains of a meal. Although gastric residues are rarely collected, according to Shourd and Winter 1980, they can be extremely abundant in some consolidated sediments. Gastric residues would be better preserved and have more finely detailed skeletal remains of prey because they hadn't been degraded as extensively by stomach acid and digestive enzymes according to Kent,1994. Plus it could better explain the vertebrae being exposed like they are in the specimens.

Marco Sr.

[MarcoSr]

I wonder is scales could be found in the details.

With the vertebrae being 1mm in this specimen, the scales would be much smaller so it is very possible that there are scales in the details. A lot of specimens have tiny flecks which I thought were tiny bone fragments but some may indeed be scales. What I don't know is if the material that scales are composed of would be easier to dissolve in the digestive stomach acid and enzymes than bone would be to dissolve.

I wish a modern researcher could chime in on what modern fish, shark and ray coprolites look like. What do they contain? Bone? Scales? Cartilage? Vertebrae? If they do contain these, how degraded are they by the stomach acids and digestive enzymes? The present can always help decipher the past.

Marco Sr.

[Al Dente]

Here is a fish scale found in a coprolite. This particular coprolite has a lot of fragmented bone. I think it is Cretaceous but was found in a lag deposit that has fossils that range from Cretaceous to Eocene. The scale is between 1 and 2 millimeters.

[MarcoSr]

Here is a fish scale found in a coprolite. This particular coprolite has a lot of fragmented bone. I think it is Cretaceous but was found in a lag deposit that has fossils that range from Cretaceous to Eocene. The scale is between 1 and 2 millimeters.

Eric

Thank you for posting this. It looks like that scale got through a digestive system totally unscathed and is in the size range of the vertebrae in my specimen. Was there any discussion of whether the coprolite was fish, shark or ray?

Marco Sr.

[Hunt4teeth]

Hey Marco, that is some cool sh!t you got there....literally! Sorry I have no other insight to add to the discussion.

Jay

[Al Dente]

Here's a web page from Oceans of Kansas that has plenty of coprolites.

http://oceansofkansas.com/coprolite.html

[MarcoSr]

Here's a web page from Oceans of Kansas that has plenty of coprolites.

http://oceansofkansas.com/coprolite.html

Eric

Thank you for the link. I've been to Oceans of Kansas a hundred times but somehow missed the coprolite page. Seeing all of the bones and vertebrae in those coprolites makes me more confident now that my specimens with all the vertebrae could have passed through a digestive tract. Plus the most interesting aspect of the coprolite page was the marine bird coprolites. So a marine bird could be the "what" that ate the fish. Wow, I wish there was some way to distinguish a marine bird coprolite.

Marco Sr.

[MarcoSr]

Hey Marco, that is some cool stuff you got there....literally! Sorry I have no other insight to add to the discussion.

Jay

Jay

I wish I knew some Paleontology or Marine Biology student who was searching for a thesis topic. I have thousands of these coprolites that could be thin sectioned and studied. That could make for a very interesting paper.

Marco Sr.